The whistling of pigeons' wings acts as an alarm call. The wings give slightly different whistles when a bird takes flight normally and when it flees from a predator. Flocks react more strongly to the latter.

New Jersey's Department of Environmental Protection opposes wind farms on the Delaware Bay because the turbines could harm natural resources. The proposed turbines would be sited close to several major migration stopover sites and potentially lie in the path of birds flying across the bay.

Conservationists are working to restore the Andean Condor population in Colombia. Currently there are about 150 condors in the wild in Colombia, supported by annual releases of captive-bred birds. U.S. zoos have underwritten most of the costs of the reintroduction program, which is coordinated by the San Diego Zoo.